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<div class="section" title="Utilities">
<div class="titlepage"><div><div><h3 class="title">
<a name="range.reference.utilities"></a><a class="link" href="utilities.html" title="Utilities"> Utilities</a>
</h3></div></div></div>
<div class="toc"><dl>
<dt><span class="section"><a href="utilities/iterator_range.html"> Class <code class="computeroutput"><span class="identifier">iterator_range</span></code></a></span></dt>
<dt><span class="section"><a href="utilities/sub_range.html"> Class <code class="computeroutput"><span class="identifier">sub_range</span></code></a></span></dt>
<dt><span class="section"><a href="utilities/join.html"> Function join</a></span></dt>
</dl></div>
<p>
        Having an abstraction that encapsulates a pair of iterators is very useful.
        The standard library uses <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></code>
        in some circumstances, but that class is cumbersome to use because we need
        to specify two template arguments, and for all range algorithm purposes we
        must enforce the two template arguments to be the same. Moreover, <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">iterator</span><span class="special">,</span><span class="identifier">iterator</span><span class="special">&gt;</span></code> is hardly self-documenting whereas more
        domain specific class names are. Therefore these two classes are provided:
      </p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
          Class <code class="computeroutput"><span class="identifier">iterator_range</span></code>
</li>
<li class="listitem">
          Class <code class="computeroutput"><span class="identifier">sub_range</span></code>
</li>
<li class="listitem">
          Function <code class="computeroutput"><span class="identifier">join</span></code>
</li>
</ul></div>
<p>
        The <code class="computeroutput"><span class="identifier">iterator_range</span></code> class
        is templated on an <a href="../../../../../../libs/iterator/doc/new-iter-concepts.html#forward-traversal-iterators-lib-forward-traversal-iterators" target="_top">Forward
        Traversal Iterator</a> and should be used whenever fairly general code
        is needed. The <code class="computeroutput"><span class="identifier">sub_range</span></code>
        class is templated on an <a class="link" href="../concepts/forward_range.html" title="Forward Range">Forward
        Range</a> and it is less general, but a bit easier to use since its template
        argument is easier to specify. The biggest difference is, however, that a
        <code class="computeroutput"><span class="identifier">sub_range</span></code> can propagate constness
        because it knows what a corresponding <code class="computeroutput"><span class="identifier">const_iterator</span></code>
        is.
      </p>
<p>
        Both classes can be used as ranges since they implement the <a class="link" href="extending.html" title="Extending the library">minimal
        interface</a> required for this to work automatically.
      </p>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2003 -2010 Thorsten Ottosen, Neil Groves<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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